The Association Between Functional Status and Health-Related Quality of Life Following Discharge from the Pediatric Intensive Care Unit

Background: Despite one third of children with acquired brain injury (ABI) experiencing new functional impairments following critical care admission, there is limited research investigating the impact of new functional impairments on overall health-related quality of life (HRQOL) or among important HRQOL domains. We aimed to investigate the association between new functional impairments, measured by the Functional Status Scale (FSS), and HRQOL in pediatric patients with ABI after critical care. Methods: We conducted a secondary analysis of a prospective observational study of 275 children aged 2 months to 18 years with ABI. The primary exposure evaluated was change in FSS from baseline at hospital discharge, categorized per prior work (no change, 1–2 point increase, and ≥ 3 point increase). The primary outcome was overall HRQOL 6 months after hospital discharge, measured by the Pediatric Quality of Life Inventory (PedsQL) total score. Secondary outcomes were PedsQL domain scores. PedsQL total and domain scores were transformed into age-standardized z scores for analyses. Multiple linear regression models evaluated the association between FSS change category and HRQOL (overall and domain z scores) when controlling for demographic and clinical characteristics and were reported as β-coefficients with 95% confidence intervals. Results: Complete data were analyzed for 195 (71%) children, including 127 with traumatic brain injury. New functional impairment was common with 32 (16%) patients experiencing FSS increases ≥ 3, 50 (26%) patients with FSS increases of 1–2 points, and 113 (58%) patients with no change from prehospital baseline. The majority of children (63%) demonstrated HRQOL ratings ≥ 1 standard deviation below healthy age-based standards (z scores ≤ − 1). Regression models demonstrated older age, female sex, presence of comorbidities, and preadmission cardiopulmonary resuscitation were all significantly associated with poorer overall HRQOL (all p < 0.05). FSS increase ≥ 3 at discharge was significantly associated with worse overall HRQOL at follow-up (β = − 1.07; 95% confidence interval = − 1.63 to − 0.52) when controlling for the aforementioned significant factors, and significantly improved model fit (p value for change = 0.001). Similar findings in secondary analyses were found for physical domain scores, with FSS increase showing a significant association with worse physical HRQOL scores and improvements in model fit. Change in FSS was not significantly associated with other HRQOL domain scores (emotional, social, school, psychosocial). Conclusions: Many children with ABI after critical care experience new functional impairments (FSS increases) and worse HRQOL than healthy peers. FSS increase at discharge is a significant risk factor for worse HRQOL in the months after hospital discharge and improves HRQOL models beyond illness and demographic variables alone.